Carbohydrates and Health

Insulin sensitivity/resistance
10.51 Four randomised controlled trials were identified that presented evidence on GL
in relation to insulin sensitivity/resistance (Pereira et al., 2004; Ebbeling et al., 2005;
Pittas et al., 2006; Maki et al., 2007). No further trials were identified in the update
search (Cardio-metabolic review, diabetes chapter).
10.52 Due to variation between trials in the method used to measure insulin sensitivity/
resistance, it is not possible to combine these trials using meta-analysis. One trial
reports an effect of GL on insulin sensitivity/resistance (Pereira et al., 2004), but the
other trials provide no evidence of an effect of GL on insulin sensitivity/resistance.
Glycaemic load and insulin sensitivity/ resistance
• No effect
• Limited evidence
Colo-rectal cancer
10.53 Nine cohort studies investigating GL were identified which provided data on
diets with a higher or lower GL and their relationship to the incidence of colorectal
cancer, all of which were included in the meta-analysis (Terry et al., 2003;
Higginbotham et al., 2004; Michaud et al., 2005; McCarl et al., 2006; Larsson et al.,
2007; Strayer et al., 2007; Howarth et al., 2008; Weijenberg et al., 2008; George
et al., 2009). One cohort study was identified in the update search (Li et al., 2011)
(Colo-rectal health review; Update search).
10.54 No significant association was found between GL and incidence of colo-rectal
cancer (RR 1.00, 95% CI 0.97, 1.03, for each 20 GL unit increase).
Glycaemic load (unit/day) and colo-rectal cancer
No association
Adequate evidence
Outcomes where there is insufficient or inconsistent
evidence 15
10.55 The tables below detail the exposures and outcomes where there are two or
fewer studies that meet the inclusion criteria for the review (e.g. by study duration,
publication date, health of subjects, design of intervention), or where the studies
are too inconsistent, to draw a conclusion as per the grading system in Annex 2.
A full description of the studies can be found in the relevant systematic reviews.
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15 See Annex 2 paragraph A2.21 for criteria.